1. Field of the Invention
This invention relates to a biocidal composition. More particularly, this invention relates to a biocidal composition comprising a blend of at least one selected pyrithione compounds and at least one selected pyrrole derivatives that prevent, or inhibit growth of microbes and the method of using such biocidal composition.
2. Brief Description of Art
Many compositions and formulations are known in the art for the prevention, inhibition, and treatment of growth or infestation of microbes. Likewise, there are many compositions and coatings specifically formulated for the prevention, inhibition, and treatment of growth or infestation of fouling organisms.
Fouling organisms present a large problem for substrates and objects that are exposed to water. The term “fouling organism” includes both hard and soft fouling organisms. Hard fouling organisms include barnacles, mollusks, and the like, while soft fouling organisms include algae, fungi, and the organisms listed in U.S. Pat. No. 5,712,275, which is incorporated by reference herein. Such organisms present a constant problem for objects and substrates that are exposed to marine water, fresh water, brackish water, sewage water, waste water, rain water, and the like.
Fouling organisms grow on, infest, or adhere to various kinds of substrates and objects that are exposed to any type of water. Growth or infestation of fouling organisms on surfaces is visually unappealing. Additionally, growth may cause some problems in using the substrates and objects that fouling organisms have attached or infested. For example, one problem that occurs frequently is the attachment of hard fouling organisms to a ship hull. The organisms cause the surface of the ship to become rough, thereby reducing the ship's speed.
Additionally, wood and wood products often experience growth and infestation of microbes such as fouling organisms, termites and the like. Growth and infestation of such microbes leads to warping, cracking, and deterioration of the wood and wood products. Consequently the wood and wood products lose value, visual appeal, and usefulness.
To combat this problem, coatings comprising biocides were developed. Examples of biocides found useful include tributylin compounds, pyrithione compounds, oxathiazine compounds, pyrrole compounds, triphenylboron compounds and terbutyn.
Pyrithione compounds and select pyrrole compounds are separately known and used as biocidal or antifouling agents. However, it is not known in the art, nor is it obvious to combine the two compounds. Examples of prior art references teaching the use of pyrithione compounds and selected pyrrole compounds include the following:
U.S. Pat. No. 5,057,153 to Ruggiero relates to an improved paint or paint base composition characterized by enhanced biocidal efficacy. The paint contains a biocide comprising pyrithione salt and a copper salt. Additionally, in U.S. Pat. No. 5,246,489 to Farmer Jr. et al. a process for generating copper pyrithione biocide in-situ in a paint formulation is disclosed. The paint and paint bases of this patent comprise pyrithione compounds as the only biocide present in the formulation.
U.S. Pat. No. 5,098,473 to Hani et al. relates to paints and paint bases, and more specifically to a process for providing a stable gel-free dispersion of zinc pyrithione plus cuprous oxide biocide in paint (see also U.S. Pat. Nos. 5,098,473; 5,112,397; 5,137,569; 5,185,033; 5,232,493; 5,298,061; 5,342,437; PCT Patent Application No. WO 95/10568 and EP 0610251).
U.S. Pat. No. 4,957,658 to French et al. related to paint and paint bases and more specifically to a process and composition for providing reduced discoloration of paints and paint bases containing a pyrithione and ferric ion.
U.S. Pat. No. 4,399,130 to Davidson et al. describes a method using an effective amount of at least one metallic salt of pyridine-2-thione-N-oxide to treat or prevent swine exudate epidermitis.
U.S. Pat. No. 4,496,559 to Henderson et al. describes selected derivatives of 2-selenopyridine-N-oxide for use as fungicides and bactericides.
U.S. Pat. No. 4,565,856 to Trotz et al. relates to pyrithione-containing polymers. The polymers described in this patent are used as biocides in paints and wood preservative products.
U.S. Pat. No. 4,610,993 to Wedy et al. describes a method of administering an effective mount of at least one selected pyridine-N-oxide disulfide compound to treat or prevent bovine mastitis.
European patent number EP 0746979 describes a method for controlling or combating the attachment of a fouling organism to an underwater surface by contacting the organism with an antifouling-effective amount of a 2-arylpyrrole compound.
U.S. Pat. No. 6,069,189 to Kramer et al., describes antifouling paints that contain selected pyrrole derivatives. Specific pyrrole compounds incorporated into the antifouling paint include 2-trihalogenomethyl-3-halogeno-4-cyano pyrrole and derivatives thereof. Kramer et al. found these compounds to be particularly effective against barnacle infestation. Additionally, this Kramer et al. reference found that bright or light colored anti-fouling paint could be created despite the addition of these compounds.
PCT Patent Application No. WO 03/039256 describes an antifouling composition that comprises an amount of at least 3.5 wt. % based on the total weight of the dry mass of the composition of 4-bromo-2-(4-chlorophenyl)-5-(trifluoromethyl)-1H-pyrrole-3-carbonitrile, or a salt thereof together with another biocide. The other biocide is selected from bethoxazin, tolylfluanide, dichlofuanide, or DCOIT.
Despite the advances made in the art, what is still needed is a coating that comprises an biocidal composition that would be effective against a large spectrum of microbes, and also demonstrates high durability and low toxicity. Ideally, the coating and the composition would be easily and inexpensively produced. This invention is believed to be an answer to the above discussed problems.